This investigation is directed towards examining the role that host immunity may play in the cure by radiation therapy of a common human cancer, squamous cell carcinoma of the uterine cervix. The data to date indicates that most, if not all patients with this tumor develop a host response against it that involves both cellular and humoral components. Radiation therapy depresses this immunity substantially but this effect is transient. Cervix cancer cells show at least one antigen in common and this antigen can be solubilized. Xenogeneic antisera can induce additional immunity in vitro. The interaction of these various immunologic parameters are under study.